The present invention relates to liquid separators for separating liquid entrained in vapor. More particularly, the present invention relates to a liquid separator assembly that is utilized as an oil separator for separating oil entrained in vapor that is emitted from an internal combustion engine. The oil is separated from the vapor and returned to the engine for use.
Conventional devices for use on internal combustion engine for separating oil entrained in vapor emitted from the engine are generally complicated devices that include a series of internal baffles and pipes. By routing the oil-entrained vapor through the series of baffles and pipes, the oil is separated from the vapor, with the oil generally returned to the engine and the vapor then routed to further processing elements, normally a crankcase ventilation valve commonly referred to as a PCV valve. In addition to the complex nature of these conventional separators, the conventional separators generally route the separated oil back into the engine through a common conduit that is also serving to route the oil-entrained vapor into the separator.
One problem with conventional separators is that they are generally expensive to produce because of the complex nature of the internal baffles and pipes that are required to separate the oil from the vapor. Another problem with conventional separators is that, because the separated oil is returned to the engine through a common conduit that is also acting to channel the oil-entrained vapor into the separator, the separated oil may be picked up by the flow of oil-entrained vapor and returned to the separator. This causes the oil-entrained vapor routed from the engine to the separator to become more oil laden, which then decreases the efficiency of the oil separator.
One object of the present invention is to produce a simplified liquid separator that is capable of separating a liquid from a liquid-entrained vapor, and that is both simple and economical to construct.
Another object of the present invention is to provide a liquid separator in which specially designed end treatments of the inlet and outlet pipes are provided. The specially designed end treatments for the inlet and outlet pipes serve to replace the various baffles and tubes normally installed in conventional liquid separators.
Yet another object of the present invention is to provide a liquid separator that incorporates a separate oil return conduit within the separator assembly.
According to the present invention, a liquid separator assembly fulfilling the above objects is provided. The liquid separator assembly of the present invention includes a housing having an interior wall that is configured to define a containment chamber. The assembly also includes a downstream or outlet pipe that is coupled to the housing and is in fluid communication with the containment chamber to discharge vapor from the housing. An upstream or inlet pipe is provided that is coupled to the housing and is in fluid communication with the containment chamber to introduce liquid-entrained vapor into the housing. The upstream pipe is formed to include expansion means which are located in the containment chamber for cooling the liquid entrained vapor discharged into the containment chamber to induce condensation of the liquid in the vapor onto the interior wall of the housing. The assembly further includes liquid return means for conducting the condensed liquid collecting in the containment chamber to a point of use.
One feature of the foregoing structure is that the separator assembly comprises as few as three components to accomplish the separation of the liquid from the liquid-entrained vapor. One advantage of this feature is that the liquid separator assembly of the present invention is much simpler than conventional liquid separators, and is therefore less expensive to manufacture.
Another feature of the foregoing structure is that the upstream pipe is formed to include expansion means located in the containment chamber for cooling the liquid-entrained vapor to induce condensation of the liquid in the containment chamber. One advantage of this feature is that the expansion means is formed to be a part of the upstream pipe, which again simplifies the assembly.
Yet another feature of the foregoing structure is that a liquid return means is provided for conducting condensed liquid collected in the containment chamber back to a point of use. One advantage of this feature is that, by providing a separate liquid return means, the condensed liquid is returned to the point of use without any communication with the liquid-entrained vapor that is flowing into the assembly.
In preferred embodiments of the present invention, the liquid return means is provided by a return pipe that extends through the upstream pipe and is in fluid communication with the containment chamber. One feature of the foregoing structure is that the return pipe extends through the upstream pipe. One advantage of this feature is that, by forming the return pipe through the upstream pipe, the condensed liquid is maintained in a separate conduit from the inflow of liquid-entrained vapor, however no external conduits or pipes are necessary to accomplish this function.
Also in preferred embodiments of the present invention, the upstream pipe is formed to include at least one exit aperture for exhausting the liquid-entrained vapor into the containment chamber. In addition, the containment chamber has a predetermined volume that is selected to produce an air-cooling expansion in close proximity to the outside of the at least one exit aperture to induce condensation of liquid entrained in the vapor onto the interior wall of the housing. One feature of the foregoing structure is that, by providing a specially designed end treatment for the upstream pipe, and by forming the containment chamber to cooperate with the specialized end treatment, a vapor or air-cooling expansion is created which induces condensation of the liquid entrained in the air to separate the liquid from the air.
Also in preferred embodiments of the present invention, the downstream pipe is formed to include at least one inlet aperture for admitting vapor from the containment chamber into the downstream pipe. One feature of the foregoing structure is that the downstream pipe includes a specialized end treatment which acts in cooperation with the upstream pipe and the containment chamber to further separate the liquid from the liquid-entrained vapor. One advantage of this feature is that all components of the assembly cooperate to separate the liquid from the liquid-entrained vapor, thereby increasing the efficiency of the assembly.
Also in preferred embodiments of the present invention, the downstream pipe is formed to include funnel means for dispensing liquid accumulating in the downstream pipe into the containment chamber. One feature of the foregoing structure is that any liquid that is separated from the liquid-entrained vapor in the downstream pipe is channeled back into the containment chamber for admission to the return pipe. One advantage of this feature is that all oil separated in the assembly is channeled through the containment chamber and into the return pipe for return to the point of use.
The liquid separator assembly of the present invention is thus capable of separating a liquid from a liquid-entrained vapor and of returning the liquid to a selected point of use. By providing specialized end treatments for both the inlet pipe and the outlet pipe, the assembly of the present invention is less complex than the conventional separator assemblies, and is thereby less expensive to produce.
Additional objects, features, and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments exemplifying the best mode of carrying out the invention as presently perceived.